Supersonic 1,200kmph jet could fly from NYC to London in 3.5hrs – and it’s just smashed a key speed and altitude test

THE supersonic jet that could fly passengers from London to New York City in 3.5hours has reached a new top speed in its latest test flight.

The XB-1 plane, from Boom Technology, completed its seventh of ten subsonic test flights yesterday, as engineers work towards making the aircraft supersonic.

It hit speeds of Mach 0.81 – or 499 knots, up from Mach 0.67 on its previous flight.

The aircraft also flew to a new max altitude, 23,015ft – some 3,000ft more than its previous test.

“XB-1 reached a new top altitude of 23,015 feet, allowing the team to perform a final cockpit pressurization test at maximum pressure differential, ensuring that it is safe to proceed up to 30,000 feet – the altitude XB-1 will fly when it reaches supersonic speeds,” the team wrote in a test flight update.

The idea is that engineers will push the plane further, and further until it reaches Mach 1, which is the speed of sound.

The flight, piloted by Tristan “Geppetto” Brandenburg, lasted approximately 55minutes.

The XB-1 made its inaugural test flight in March this year.

It’s unclear when Boom will commence the eighth test flight, however, it could be in as little as two weeks’ time.

Boom conducted two test flights just a week or two apart in September and October, so there could be another quick turnaround.

Aerospace firms worldwide are racing for the chance to build the ‘Son of Concorde’ – the successor to the British supersonic jet that was banned in 2003.

Commercial supersonic flight over land has been banned in the US for more than 50 years, and about 20 years in the UK, because of the noise of sonic booms.

There have been no commercial aircraft even capable of hypersonic or supersonic flight since the Concorde.

The aircraft were banned in the UK because they were deemed too noisy and extremely expensive to operate.

With restricted flight availability, fares were often too high for most customers.

But with several manufacturers – including Nasa and Lockheed Martin – actively developing new supersonic aircraft, the UK’s aerospace watchdog has said it will review the ban.

However, one front-running aircraft has just dropped out of the race.

Reaction Engine, the company behind the UK’s hypersonic jet, collapsed in late October – meaning its 4,000mph aircraft is grounded for good.